Missouri certifies class action over grain-free dog food and DCM: full analysis

A Missouri court has certified a class action targeting Schell & Kampeter, Inc., doing business as Diamond Pet Foods and Taste of the Wild, in litigation over whether the company falsely marketed its grain-free dog food as safe and healthy despite an alleged link to canine dilated cardiomyopathy. The certified class covers certain Missouri consumers who purchased Taste of the Wild grain-free dog food in Missouri between August 27, 2015, and June 21, 2024. Defendant denies the allegations, and the court notice makes clear there is no recovery available at this stage and no finding yet that the company did anything wrong. (missouridogfoodclassaction.com)

The case lands in a debate that has been running since July 2018, when FDA announced it was investigating reports of DCM in dogs eating certain diets, many labeled grain-free and containing high proportions of peas, lentils, other pulses, and/or potatoes. In its most recent public update, posted December 23, 2022, FDA said it did not intend to release further public updates until there was meaningful new scientific information to share. The agency also said adverse event numbers alone do not establish a causal relationship, while maintaining that the possible diet-DCM association appears to be a complex scientific issue that may involve multiple factors. (fda.gov)

According to the amended petition, plaintiffs argue that Taste of the Wild grain-free products were promoted as high-quality, safe, and healthy while omitting information about an alleged increased risk of developing or worsening DCM. The filing says Schell & Kampeter became aware of the connection at least by July 12, 2018, when FDA announced its investigation, and alleges the company continued to conceal material facts from Missouri consumers. Those are allegations, not findings, but class certification means the case can proceed on a class-wide basis rather than only through individual claims. (missouridogfoodclassaction.com)

The broader scientific record remains mixed, which is part of what makes this case notable for veterinary teams. A prospective JVIM study found that some clinically healthy dogs with subclinical cardiac biomarker or echocardiographic abnormalities improved after switching from grain-free diets to grain-inclusive diets. A separate retrospective study of dogs with DCM and congestive heart failure reported better survival among dogs eating nontraditional diets that were changed after diagnosis, compared with dogs that continued those diets. At the same time, newer work has continued to test competing hypotheses about the role of grain-free formulation itself versus other factors such as pulses, fiber fractions, processing, nutrient bioavailability, or formulation quality. (academic.oup.com)

Professional guidance has generally stayed cautious rather than absolute. AAHA’s diet-associated DCM resource advises clinicians to take a detailed diet history and escalate diagnostics when dogs show signs such as a new murmur, arrhythmia, or exercise intolerance. Commentary from veterinary cardiology and nutrition circles has also emphasized that some affected dogs improve with diet change and treatment, while the exact mechanism remains unresolved. That leaves clinicians balancing scientific uncertainty with practical risk management in the exam room. (aaha.org)

Why it matters: For veterinarians, this lawsuit is less about a final answer on causation than about the persistence of consumer scrutiny around grain-free diets. Pet parents may interpret class certification as proof that grain-free diets cause DCM, but that’s not what the court has decided, and it’s not what FDA has concluded. Practices may need to explain that legal claims, regulatory signals, and clinical evidence are overlapping but distinct. The practical takeaway is still familiar: obtain a full diet history, especially in dogs with murmurs, arrhythmias, reduced exercise tolerance, syncope, or breeds at known cardiac risk; consider whether a boutique, exotic-ingredient, pulse-rich, or grain-free diet could be relevant; and frame recommendations around evidence, not marketing. (missouridogfoodclassaction.com)

The case also underscores how unresolved nutrition controversies can migrate into the courtroom and shape client expectations long before regulators or researchers reach firm conclusions. That matters for hospitals fielding questions from worried pet parents, for nutrition consult services, and for industry players whose branding leans heavily on ingredient narratives. If plaintiffs ultimately prevail or the parties settle, the outcome could influence how pet food companies message grain-free formulations and health claims even beyond Missouri. That last point is an inference based on the class action’s focus on marketing representations and the broader history of related pet food litigation. (missouridogfoodclassaction.com)

What to watch: The next signals are legal and scientific: whether the Missouri case moves to judgment or settlement after certification, whether any appeals narrow the class, and whether ongoing research funded through academic and canine health channels produces the “meaningful new scientific information” FDA has said it is waiting for before speaking publicly again. (missouridogfoodclassaction.com)